donation. 1  an act or instance of presenting something as a gift, grant, or contribution. 2  a gift, as to a fund; contribution.
A black or brown tongue typically is due to the overgrowth of bacteria that normally are present on the tongue. This, too, can be caused by the killing of some bacteria with antibiotics so other bacteria overgrow. But the most common cause of discoloration of the tongue is the overgrowth of a fungus. The most common fungus is called candida. But overgrowth of the candida fungus turns the tongue white. Infection with candida is called candidiasis, and when it happens on the tongue the condition is called thrush.
Tongue injuries (piercings and dental appliances) are a possible cause of black patches on your tongue especially if the injury cause sores. You can also end up with dark spots on tongue from biting or after biting your tongue. Anemia. Anemia is another possible cause of black tongue spots. Many people have reported this problem.